Lommel et al., U.S. Pat. No. 1,936,985 (1933) (incorporated herein by reference), disclose the production of certain phosphorus and phosphoric acid esters which may contain halogen. It is taught that the compounds reduce the flammability of organic materials if incorporated therein.
Birum et al., U.S. Pat. No. 3,132,169 (1964) (incorporated herein by reference), disclose the preparation of certain phosphate esters which contain both chlorine and bromine. It is taught that polyurethanes, for example, insulating foams and resin bases for curable coatings and adhesives, may be made flame-retardant by the addition of the phosphate esters in amounts from 2 percent to 25 percent by weight of the polyurethane. It is also taught that simultaneous plasticizing results and the use of the phosphate esters in the polyurethane foams taught therein (i.e., rigid foams) can increase flexibility and in some applications improve the mechanical properties of the foams.
Stanabach et al., U.S. Pat. No. 4,046,719 (1977) (incorporated herein by reference), disclose that certain trihaloneopentyl-containing haloalkyl phosphate esters are flame retardants for normally flammable resinous compositions. It is taught that tribromoneopentylbis(mono- or dichloro C.sub.2-4 alkyl)phosphates, tribromoneopentyl(mono- or dichloro C.sub.2-4 alkyl)phenyl phosphates and bis(tribromoneopentyl) (mono- or dichloro C.sub.2-4 alkyl)phosphates impart non-scorch and non-drip characteristics to foams.
Albright, U.S. Pat. No. 4,240,953 (1980) (incorporated herein by reference), disclose certain hydrogen-, chloro- and bromo-substituted neopentylbis(dihaloalkyl)phosphates (halo:chloro; bromo). It is disclosed that certain bis(dichloroalkyl)phosphates possess light-stability properties and that when the substituted neopentyl group is 2,2-dimethyl-3-halopropyl, the phosphates are of relatively low viscosity.
Albright et al., U.S. Pat. No. 4,083,825 (1978) (incorporated herein by reference), disclose that certain hydrogen-, chloro- and bromo-substituted neopentylbis(chloro-containing C.sub.2-3 alkyl)phosphates substantially solve the problem of scorch in flame-retardant polyurethanes.
What is lacking and which is needed is another process to prepare halogenated phosphorates which can be used to prepare such phosphorates. The process shoudl be efficient and selective.